ECU 6CU Circuit Diagrams

Dear enthusiasts,

Fiddling around with the ECU 6CU from my 1983 XJ12 HE, emission system B (see https://forums.jag-lovers.com/t/flooding-protection-system-xj12-iii-h-e), getting hand on the wiring diagrams of the device would make everything much easier. I am not talking about the diagrams showing the connections of the unit to the engine etc., but the circuits of the two boards inside. Does anyone have these schematics and would be willing to share them with me, or probably even sell them to me? It would certainly save me a huge amount of time.

Regards,
Florian

We all thank @RogerBywater for putting all this valuable info online.

Aristides: Thanks for the quick reply. However, that’s not exactly what I’m looking for. The diagrams at AJ6 are the same you will find in the workshop manual – they inform about the connections between the ECU and different components of the car. It is great that Roger Bywater put them online, but in my case they do little help. I try to fix a minor bug inside the ECU, so what would come in handy are schematics for the intestines of the 6CU. I did some googleing, but wasn’t able to find them until now.

Regards,
Florian

Hi Florian,
Yes I missed this, and you clearly mentioned it in your first post.
The only one that I can think of that could have this info is again Roger Bywater.

If you are asking this I presume that you have a deep knowledge of electronics?
These ECUs usually suffer either from bad/cold solder joints or failing electrolytic capacitors.
You could also check or change the power transistors, but there is were my expertise stops…

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I agree with you, Aristides - a visual inspection, starting specifically from pin #15 may be the best way forward…?

Frank
xj6 85 Sov Europe (UK/NZ)
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Resoldering/Reflowing did the trick! Now everything seems OK. I cannot precisely say which connection was faulty, but as it works, that doesn’t matter anyway.

Thanks for the advice!

2 Likes

Well done, Florian - and thanks for telling us

Frank
xj6 85 Sov Europe (UK/NZ)
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